[FFmpeg-devel] [PATCH 2/2] avcodec/tiff: Fix integer overflows in left shift in init_image()

[Michael Niedermayer]

Fixes: left shift of 255 by 24 places cannot be represented in type 'int'
Fixes: 11377/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_TIFF_fuzzer-5694319101476864

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
---
 libavcodec/tiff.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/libavcodec/tiff.c b/libavcodec/tiff.c
index 6271c937c3..64a3261fd9 100644
--- a/libavcodec/tiff.c
+++ b/libavcodec/tiff.c
@@ -706,7 +706,7 @@ static int init_image(TiffContext *s, ThreadFrame *frame)
         s->avctx->pix_fmt = s->palette_is_set ? AV_PIX_FMT_PAL8 : AV_PIX_FMT_GRAY8;
         break;
     case 10081:
-        switch (s->pattern[0] | (s->pattern[1] << 8) | (s->pattern[2] << 16) | (s->pattern[3] << 24)) {
+        switch (s->pattern[0] | (s->pattern[1] << 8) | (s->pattern[2] << 16) | ((unsigned)s->pattern[3] << 24)) {
         case 0x02010100:
             s->avctx->pix_fmt = AV_PIX_FMT_BAYER_RGGB8;
             break;
@@ -721,7 +721,7 @@ static int init_image(TiffContext *s, ThreadFrame *frame)
             break;
         default:
             av_log(s->avctx, AV_LOG_ERROR, "Unsupported Bayer pattern: 0x%X\n",
-                   s->pattern[0] | s->pattern[1] << 8 | s->pattern[2] << 16 | s->pattern[3] << 24);
+                   s->pattern[0] | s->pattern[1] << 8 | s->pattern[2] << 16 | (unsigned)s->pattern[3] << 24);
             return AVERROR_PATCHWELCOME;
         }
         break;
@@ -741,12 +741,12 @@ static int init_image(TiffContext *s, ThreadFrame *frame)
             break;
         default:
             av_log(s->avctx, AV_LOG_ERROR, "Unsupported Bayer pattern: 0x%X\n",
-                   s->pattern[0] | s->pattern[1] << 8 | s->pattern[2] << 16 | s->pattern[3] << 24);
+                   s->pattern[0] | s->pattern[1] << 8 | s->pattern[2] << 16 | (unsigned)s->pattern[3] << 24);
             return AVERROR_PATCHWELCOME;
         }
         break;
     case 10161:
-        switch (s->pattern[0] | s->pattern[1] << 8 | s->pattern[2] << 16 | s->pattern[3] << 24) {
+        switch (s->pattern[0] | s->pattern[1] << 8 | s->pattern[2] << 16 | (unsigned)s->pattern[3] << 24) {
         case 0x02010100:
             s->avctx->pix_fmt = s->le ? AV_PIX_FMT_BAYER_RGGB16LE : AV_PIX_FMT_BAYER_RGGB16BE;
             break;
@@ -761,7 +761,7 @@ static int init_image(TiffContext *s, ThreadFrame *frame)
             break;
         default:
             av_log(s->avctx, AV_LOG_ERROR, "Unsupported Bayer pattern: 0x%X\n",
-                   s->pattern[0] | s->pattern[1] << 8 | s->pattern[2] << 16 | s->pattern[3] << 24);
+                   s->pattern[0] | s->pattern[1] << 8 | s->pattern[2] << 16 | (unsigned)s->pattern[3] << 24);
             return AVERROR_PATCHWELCOME;
         }
         break;
-- 
2.19.1